FEM Modeling of Multilayer Piezo-magnetic Structure Based Surface Acoustic Wave Devices for Magnetic Sensor

Abstract

This study describes the implementation of accurate and fully coupled physics models leading to investigate Surface Acoustic Wave (SAW) devices sensitivity to an extern applied magnetic field. The model was firstly validated using experimental published data of SAW resonator based on Quartz substrate and Nickel Interdigital Transducers (IDT). Original layered structures, Ni/ZnO/IDT/LiNbO3 and Ni/Al2O3/IDT/LiNbO3 were then investigated and optimized to enhance their sensitivity to magnetic field intensity. Results show that Ni/Al2O3/IDT/LiNbO3 exhibits a sensitivity of 10 ppm/mT, 14 times higher than the structure with ZnO one.